Hush kits developed by Stage III Technologies for Rolls-Royce Spey-powered Gulfstreams are back with a new name and a new company. Yesterday at Van Nuys Airport in California, Hush Kit LLC, an affiliate of Hubbard Broadcasting of Minneapolis, flew the first production Stage III hush kit installed on a Gulfstream II (N20H), also owned by Hubbard, in preparation for the product’s debut at the NBAA Convention in Orlando, Fla., early next month.
The market for Gulfstream hush kits stands at fewer than 400 GIIs, GIITTs, GIIBs and GIIIs. These models are currently one of the softer areas of a soft market. This net number takes into account the 14 GIIs and five GIIIs written off over the years, as well as nearly 50 combined models that are serving in some government role and, due to the nature of their operation, would probably not need to conform to any noise requirements.
The race is heating up in the Gulfstream hush kit market, as three providers maneuver for the inside track. Stage III Technologies and Quiet Technologies Aerospace (QTA) continue their respective and long-time efforts to obtain STCs for hush kits for the Gulfstream II and III.
The European Commission (EC) has issued revised noise proposals that abandon its earlier demands for a blanket ban on hush-kitted aircraft with mtow of more than 75,000 lb using any airports in the 15-state European Union (EU) after this coming April. But the new draft directive, published on November 28, leaves open the possibility of a limited number of individual airports being able to exclude or restrict “marginal Stage 3” aircraft.
Legislation to ban certain large transport aircraft that have hush kits from using all European airports starting next April has been scrapped by the European Union. Consequently, the U.S. withdrew a formal complaint submitted last year to the International Civil Aviation Organization. The U.S. maintained that the regulation, that applied to hush-kitted aircraft over 75,000 lb mtow, discriminated against U.S. manufacturers.
Miami-based Quiet Technology Aerospace is nearing completion of about 45 hr of planned flight testing of its first FAA-conforming Stage 3 hush kit for Gulfstream IIs and IIIs. Flight testing of a GII equipped with the company’s translating-ejector type hush kit started in late May and follows 30 hr of baseline flight testing of the aircraft without the hush kit installed.
Making jet aircraft acceptably quiet can be a dirty job. Owners don’t want to spend the money, engine makers don’t want to compromise their products’ efficiencies and airport neighbors are rarely happy with the results.
Stage III Technologies on February 8 ceased operations pending further funding, leaving just one company–Miami-based Quiet Technology Aerospace–currently providing hush kits for the Gulfstream II and III. Stage III’s hush kit
Raytheon Aircraft announced a lightweight interior modification for its Premier I that the company says reduces cabin average noise level to 82.2 dBA on takeoff and 73.6 dBA during long-range cruise.
U.S. and European Union officials are making last-ditch efforts to negotiate a settlement to their long-running dispute over hush kits bringing Stage 2 aircraft into compliance with current Stage 3 noise limits. Both sides want the deeply divisive matter resolved at the September 25 meeting in Montreal of the International Civil Aviation Organization assembly.